When to plant in Dover, NJ
USDA Zone 6bEverything below — frost dates, hardiness zone, and what to plant when in Dover, New Jersey — is derived from the closest NOAA station with complete climate normals.
Zone 6b means Dover sees real winter cold, but a good range of perennials survive; the frost dates above govern when annual vegetables go out.
The average first fall frost in Dover is now 6 days later than in the 1981–2010 normals. See how frost dates are shifting nationwide →
Frost probability
BOONTON 1 SE · 1991–2020The date the last spring and first fall frost occur, by threshold and probability. A 90% date is later in spring — and earlier in fall — than a 10% date; the 50% · 32°F row is what most gardeners plan around. These are Dover’s own odds, recorded at BOONTON 1 SE.
| Threshold | SPRING 10% | SPRING 50% | SPRING 90% | FALL 10% | FALL 50% | FALL 90% |
|---|---|---|---|---|---|---|
| 36°F | May 18 | May 1 | Apr 17 | Oct 1 | Oct 12 | Oct 29 |
| 32°F | May 5 | Apr 17 | Apr 4 | Oct 8 | Oct 23 | Nov 6 |
| 28°F | Apr 18 | Apr 4 | Mar 21 | Oct 19 | Nov 2 | Nov 17 |
Download this table as CSV ↓ — every threshold and probability, plus this city’s planting-window dates.
What to plant now
TODAY · JULY 19Full-year planting calendar
Each bar is the exact window to take a planting action in Dover, drawn to the day from the local frost dates. The dashed line is today.
Nearby weather stations
3 within 20 km · complete 32°F normalsWhen stations disagree by more than a few days, that spread is real microclimate variation — elevation, water, urban heat. Judge which station best matches your own yard.
Dover planting FAQ
When is the last spring frost in Dover, NJ?
On average, the last spring frost in Dover is around April 17 (50% probability at 32°F, from 1991–2020 NOAA normals). Wait until after this date to set out tender plants like tomatoes and peppers.
When is the first fall frost in Dover, NJ?
In Dover, the first 32°F freeze of fall lands around October 23 on average. Time your last harvests and any season-extension cover before it.
What hardiness zone is Dover in?
Dover is in USDA hardiness zone 6b. In zone 6b, winters are moderate — most common vegetables grow well in season.
How long is the growing season in Dover?
There are roughly 189 frost-free days in Dover (a moderate growing season), running from the average last frost around April 17 to the first fall frost near October 23.
When should I plant tomatoes in Dover?
In Dover, start tomato seeds indoors around February 20–March 6, then transplant seedlings outdoors around April 24 once the danger of frost has passed.
Never miss a window in Dover
An email when it’s time to start seeds, transplant, and sow — timed to Dover’s frost dates. Double opt-in, one-click unsubscribe, no spam.
Nearby cities
8 within reach- Lake Hopatcong · 9 km
- Hopatcong · 11 km
- Morristown · 12 km
- Parsippany · 13 km
- Lake Hiawatha · 15 km
- Budd Lake · 15 km
- Oak Ridge · 17 km
- Kinnelon · 18 km
Frost dates recorded at BOONTON 1 SE, 14 km from the city center · 1991–2020 NOAA climate normals · zone from the USDA/PRISM 2023 map. How we compute this.
BlissGarden. "When to Plant in Dover, NJ — Frost Dates & Zone 6b." Frost normals: NOAA NCEI U.S. Climate Normals 1991–2020, station USC00280907. Retrieved from https://blissgarden.com/new-jersey/dover.